Transcript Classification - Cobb Learning

Ch.17 – Organizing Life’s Diversity
17.1 – History of Classification
Taxonomy – branch of biology concerned with
identifying, naming, and classifying species
Based on a system
developed by Carolus
Linnaeus in 1748
Linnaeus’ system involved classifying
organisms in a series of groups from
large and general to smaller and more
specific according to physical
characteristics
He also developed a two-part
naming system for every
species
Ch.17 – Organizing Life’s Diversity
17.1 – History of Classification
Human Classification
Eukaryotic, heterotrophic,
multicellular
Animalia
Vertebrates
Chordata
Milk-producing, fur/hair
covered
Mamalia
Short snouts, stereoscopic vision,
Primata
nails not claws, 4 types of teeth
Bipedal, large frontal
lobes of brain
Hominidae
Larger brain (>1000cc), upright
forehead, shorter arms, longer
legs, language, culture
High forehead, small teeth
and jaw, defined chin, and
ability to create and
appreciate art/symbols
Homo
Sapiens
Used as the scientific names for all
species (Binomial Nomenclature)
Ch.17 – Organizing Life’s Diversity
17.2 – Modern Classification
Species are classified today according to
physical and genetic characteristics
Phylogenetic tree shows evolutionary
relationships based on
similarities and
differences in physical
and/or genetic
characteristics.
There is presumed to
be a common ancestor
at each node and the
distance between
nodes indicates the
passage of time
Ch.17 – Organizing Life’s Diversity
17.2 – Modern Classification
Cladogram - shows one branch of a phylogenetic tree and
focuses mainly on homologous structures of the organisms
Derived trait – A trait not
present in the last common
ancestor being considered
Ancestral trait – Traits
retained from common
ancestors
17.3 – Domains and Kingdoms
Ch.17 – Organizing Life’s Diversity
The 3 Domains and 6 Kingdoms
Eukarya
Plantae
Fungi
Animalia
Protista
Archaea
Bacteria
Eubacteria Archaebacteria
17.3 – Domains and Kingdoms
Ch.17 – Organizing Life’s Diversity
Archaebacteria
Eubacteria
Protista
Prokaryotic
Unicellular
Hetero- or
Autotrophic
Prokaryotic
Unicellular
Hetero- or
Autotrophic
Eukaryotic
Uni- or Multicellular
Hetero- or
Autotrophic
-Live in extreme
environments
-Most bacteria found
on Earth
-Usually found in
aquatic environments
Fungi
Plantae
Animalia
Eukaryotic
Uni- or Multicellular
Heterotrophic
(Decomposers)
-Absorb nutrients
from other organic
material
Eukaryotic
Multicellular
Autotrophic
Eukaryotic
Multicellular
Heterotrophic
-Have tissues
organized into organs
and organ systems
-Most are mobile
-Have cells organized
into tissues
-Most are immobile
17.3 – Domains and Kingdoms
Ch.17 – Organizing Life’s Diversity
What about Viruses?
Viruses containing RNA are
called retroviruses
-Viruses are non-living.
-They are DNA or RNA surrounded by a protein coat (capsid) and
are sometimes enclosed within a membrane
-A virus needs a host to
reproduce
-Outside of a host a virus is
metabolically inert
HIV
(a retrovirus)
-The virus inserts its genetic
material into the host, taking
over the host’s functions.
-An infected cell creates more
viral protein and genetic
material.
Ch.17 – Organizing Life’s Diversity
17.3 – Domains and Kingdoms
What about Viruses?
Viral Diseases
-A virus may
remain
dormant for a
period of time
causing no
changes in the
host cell, called
the lysogenic
phase
-Common Cold
-Influenza
-Chicken Pox
-Herpes (I & II)
-AIDS
-But when
stimulated, it
enters the lytic
phase:
new viruses are
formed, selfassemble, and
burst out of the
host cell, killing
the cell and
going on to
infect other cells